Dear Allison,
Thanks for using the Portfolio Manager. Each theme has different page widths, so the following solution is specifically for your case.
The centering of the mosaic can be done by adjusting the width of the main portfolio wrapper DIV, .eds-bpm-main and making it same width as the portfolio elements inside it. e.g. for full-screen size we make the .eds-bpm-main 's width equal to 5 portfolio items, for smaller screens, 3 items, 2 items and so on.
Following CSS should work in your case. Please paste it in
Portfolio Manager > Settings > Advanced Tab > Custom CSS Textbox
.eds-bpm-main {
max-width: 1150px;
margin-left: auto;
margin-right: auto;
}
@media only screen and (min-width: 1070px) and (max-width: 1269px) {
.eds-bpm-main {
max-width: 920px;
}
}
@media only screen and (min-width: 960px) and (max-width: 1069px) {
.eds-bpm-main {
max-width: 690px;
}
}
@media only screen and (min-width: 530px) and (max-width: 959px) {
.eds-bpm-main {
max-width: 460px;
}
}
@media only screen and (max-width: 529px) {
.eds-bpm-main {
max-width: 230px;
}
}
Please let me know if this works.